Seasonal Outlook - June to August 2016

El Nino Southern Oscillation (ENSO)

Recent observations showed that El Niño continues to weaken and conditions are favourable for La Niña to evolve during the up-coming months. Sea-surface temperatures (SSTs) in the Eastern Equatorial Pacific Ocean was less than 1°C above average (NINO3.4).

Most of the models predict the end of El Niño and a brief period of ENSO-neutral by early Northern Hemisphere summer with >50% chance of La Niña conditions by June-July-August increasing to 75% for September-October-November.

Figure 6: Forecasts of sea surface temperature (SST) anomalies for the Nino 3.4 region
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CPC/IRI ENSO Probability Forecast
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Regional Overview on Seasonal Forecasts for June - August 2016

Rainfall Outlook

Precipitation Outlook for the Caribbean June - August 2016
Precipitation Outlook for the Caribbean June - August 2016

Above to normal rainfall totals are forecast for Dominica for June-July-August 2016.

Probability:

  • 40% chance of above normal
  • 35% chance normal
  • 25% chance of below normal

Wet Days and Wet Spells Outlook

June - August 2016 Wet Days Frequency Shift
Table 1: June - August Wet Days(>1.0mm) Frequency Shift
Station Climatology (Wet days) Forecast (Wet days)
Canefield Airport 49 to 67 46 to 64
Douglas-Charles 53 to 70 52 to 67

Forecast: Fewer wet days than normal (low to medium confidence).

Implication: Increasing surface wetness as we move from the dry to the wet season and disruptions of outdoor activities (however perhaps less often than usual).

June - August 2016 frequency of 7-day wet spells
Table 2: June - August 7 Day Wet Spells Frequency Shift
Station Climatology (7 day wet spell) Forecast (7 day wet spell)
Canefield Airport 3.9 to 7 2.2 to 5.6
Douglas-Charles 3.2 to 6.6 1.5 to 4.7

Forecast: Fewer 7 day wet spells than normal (medium confidence).

June - August 2016 Extreme 3 Day Wet Spells Frequency Shift
Table 3: June - August 3 Day Extreme Wet Spells Frequency Shift
Station Climatology (3 day extreme wet spell) Forecast (3 day extreme wet spell)
Canefield Airport 0 to 1.3 0
Douglas-Charles 0 to 1.5 0

Forecast: There is an increased chance of 3-day extreme wet spells (medium to high confidence).

Implication: Flash flood potential developing.

Drought Outlook

June - August 2016 Drought Alert

There are no drought concerns for Dominica up to August 2016.

Temperature Outlook

Temperature Outlook for the Caribbean June - August 2016
Temperature Outlook for the Caribbean June - August 2016

Air temperatures are expected to be above to normal. Night and day-time temperatures are expected to be warmer.

Minimum/ night-time temperature Probability

  • 45% chance of above normal
  • 35% chance normal
  • 20% chance of below normal

Maximum/ day-time temperature Probability

  • 50% chance of above normal
  • 30% chance normal
  • 20% chance of below normal